JPH06524U - Punch - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a punch capable of surely making a smooth hole even with a thick iron plate or a stainless steel plate and stably perforating an end portion of the plate. [Structure] A top surface portion that receives a downward load of a punching machine, a cylindrical throttle portion having a reduced diameter on the top surface portion, a reverse punched circular punch projecting from the lowermost end of the throttle portion, and a circular punch It consists of a projection for positioning the tip, and the lower side of the throttle part has an inverted conical shape, while the round punch is set longer than the length of the throttle part. Cold punched steel is used as the material for the punch, and vacuum quenching is performed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improved punch for punching a steel plate or a stainless steel plate.

[0002]

[Prior art]

 Conventionally, a punch and a die as shown in Fig. 1 have been used for drilling a steel plate or the like. Here, 1 is a punch, which is used for aligning the top surface portion 3 having a shallow depression 2, the narrowed portion 4 following this, the round punch 5 projecting below it, and the lower surface center of the round punch 5. It consists of protrusions 6. In addition, the lower side of the narrowed portion 4 is narrowed to have an R-shaped cross section, and the round punch 5 is provided with a relief angle in an inverse tapered shape. Next, a die 7 is provided with a hole 9 1 into which the round punch 5 is fitted, at the center of the top of a die main body 8 having a cylindrical shape with a lid. The punch 1 and the die 7 are respectively gripped by a punch holder and a die holder (not shown) of the punching machine. Then, an iron plate is sandwiched between the punch 1 and the die 7 and a downward load is applied to the punch 1 by means of a cam or the like to form a hole of a predetermined size.

[0003]

[Problems to be solved by the device]

 The material of the above conventional product is steel carbon such as SK5, and the quenching after processing must be water quenching. However, since the punch 1 has an uneven shape as a whole, it is difficult to uniformly quench the punch 1, and the hardness of the round punch 5 and the top surface portion 3 and the narrowed portion 4 becomes uneven after quenching. The longer the length, the easier it is to break the neck. Therefore, the length of the round punch 5 was made as short as possible to prevent it from breaking. The length of the punch is determined by the stroke of the punching machine, which is generally constant, and therefore the height of the punch 1 itself is also constant (66 mm). Therefore, if the round punch 5 is shortened, the length of the throttle portion 4 must be relatively lengthened.

By the way, as shown in FIG. 2, when the punch 1 and the die 7 are used to form a hole in the iron plate P, the punch 1 is pressed against the iron plate so that the die 7 side is provided around the hole. Deformation strain occurs toward it. When the punch 1 is returned after the round punch 5 penetrates the iron plate, the iron plate is pulled up because the round punch 5 has a reverse taper shape. Therefore, in this type of punch and die, generally, a support plate 10 is applied between the iron plate P and the narrowed portion 4 of the punch 1, and the support plate 10 presses the iron plate P when pulling up the punch 1. However, since the circular punch 5 is short, when the support plate 10 is applied, the vertical stroke is further shortened by the thickness, and the thickness of the iron plate that can be processed is limited. Further, since the lower side of the narrowed portion 4 has an R-shaped cross section, the contact with the support plate 10 is point contact, which is unstable. In particular, when drilling at the edge of the iron plate, one of the support plates protrudes from the iron plate, so the support plate may come off if the contact is unstable. It should be noted that such an obstacle is more likely to occur as the iron plate is thicker or the diameter of the round punch is larger.

The present invention is intended to solve the problems of the conventional example as described above, and it is possible to surely make a smooth hole even with a thick iron plate or a stainless steel plate, and stably perforate the end part of the plate. The purpose of the present invention is to provide a punch that can be used.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, in the present invention, a top surface portion that receives a downward load of a punching machine, a cylindrical throttle portion whose diameter is reduced, and an inverted taper shape protruding from the lowermost end of the throttle portion are provided. It consists of a round punch and a projection for positioning the tip of this round punch.While the lower side of the throttle section has an inverted conical shape, the means for setting the round punch longer than the length of the throttle section is used. I was there. As the punch material, cold die steel was used and vacuum quenching was adopted.

[0007]

[Action]

 By shortening the length of the throttle and lengthening the round punch by that amount, the vertical stroke of the round punch is increased. This increases the piercing speed by the round punch and has the function of smoothing the piercing cross section. Also, by adopting cold die steel, the hardness of the punch increases, and at the same time, vacuum quenching ensures uniform quenching, so even if the round punch is lengthened, the neck is hard to break. It is something to do.

[0008]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 3 is a vertical sectional view of the punch 30. First, the punch 30 has basically the same structure as the conventional example, 31 is a top surface portion that is gripped by a punch holder and receives a downward load of the punching machine, and 32 is a columnar shape having a reduced diameter of the top surface portion 31. A diaphragm part, 33 is a round punch, and 34 is a projection for alignment. Edge processing is applied around the lower end of the round punch 33, and an iron plate or the like is cut off by this edge. The basic structure of these is the same as the conventional example. The depression 2 in the conventional example is not always necessary.

Next, the characteristic points of this embodiment will be described. The lowermost surface 35 of the throttle portion 32 has a conical shape instead of the R-shaped cross section as in the conventional example. ing. Further, regarding the height (length) of each portion, in this embodiment, the narrowed portion 32 is set to be relatively short, and the round punch 33 is lengthened accordingly. As described above, the length of the punch 30 is fixed (66 mm) due to the vertical stroke of the cam of the punching machine, and the total length of the throttle portion 32 and the round punch 33 is constant. Therefore, if the narrowed portion 32 is lowered, the round punch 33 can be lengthened, whereby the punching stroke of the round punch 33 with respect to the iron plate is lengthened. That is, since the moving speed of the edge at the time of cutting is high, the cross section of the iron plate is smooth.

Next, cold die steel (DS53) was used as the material of the punch 30 of the present embodiment. Then, the cold die steel was cut into a punch shape and then vacuum hardened to increase the hardness. Depending on the physical properties of the material itself and the quenching method, the punch 30 has a uniform and high hardness after quenching as compared with the conventional example, and the disadvantage that the neck portion of the round punch 33 is broken can be eliminated. In addition, as described above, the round punch 33 is lengthened to lengthen the piercing stroke, so that the piercing cross section of the iron plate becomes smoother, and fatigue can be delayed.

FIG. 4 is a cross-sectional view of a die suitable for the punch 30 of the present embodiment. Reference numeral 40 denotes the die body, which has a cylindrical shape with a lid. Reference numeral 41 is a hole into which the round punch 33 is fitted, and forms a taper surface which is spread slightly downward. A play is provided in the diameter of the round punch 32 and the diameter of the hole 41. For example, a punch having a 11 mm diameter round punch is combined with a die having a 12 mm diameter hole. The die material is made of cold die steel together with the punch.

Although the circular punch 33 has a perfect circular cross section in the above-described embodiment, the essential structure is the same for an elliptical punch for making an elliptical hole. In this case, the circular punch 33 has an elliptical cross section, but these embodiments are also included in the scope of the present invention. In that case, of course, the hole 41 of the die 40 must also have an elliptical shape suitable for this.

[0013]

[Effect of device]

 As described above, the punch of the present invention has a top surface portion that receives a downward load of the punching machine, a cylindrical throttle portion having a reduced diameter on the top surface portion, and an inverted taper shape protruding from the lowermost end of the throttle portion. Regarding the basic structure consisting of a round punch and a projection for positioning the tip of this round punch, the lower side of the throttle part has an inverted conical shape, while the length of the round punch is longer compared to the length of the throttle part. Cold die steel was vacuum quenched. Therefore, it is possible to provide a punch that can withstand long-term use because it is possible to make a smooth hole in an iron plate and the hardness of the punch is high so that the edge of the round punch is less likely to set. Moreover, it was possible to easily punch holes in stainless steel plates, which was very difficult in the past, and it was possible to create a punch with less edge fatigue.

Further, since the round punch is elongated, the punching stroke can be sufficiently secured even if there is a supporting plate generally used for processing, and reliable drilling is possible. In addition, even when processing the end of the iron plate, the lower side of the punched part has a straight cross-section, so it is in stable contact with the support plate, enabling reliable drilling.

[Brief description of drawings]

FIG. 1 is a perspective view of a conventional punch and die,

FIG. 2 is a cutaway end view of a central portion showing a practical use example of a conventional example,

FIG. 3 is a sectional view showing an embodiment of the punch of the present application,

FIG. 4 is a cutaway end view of a central portion of a die used in combination with a punch of the present application;

FIG. 5 is a central cut end view showing a practical example of use of the punch of the present application.

[Explanation of symbols]

 30 Punch 31 Top Surface Part 32 Drawing Portion 33 Round Punch 34 Protrusion 35 Lowermost Surface 40 Die Body 41 Hole

Claims (1)

[Scope of utility model registration request] 1. A punch for punching a metal plate or the like, comprising:
Positioning of the top surface of the punching machine that receives the downward load, a cylindrical throttle with a reduced diameter on this top, a reverse tapered circular punch protruding from the lowermost end of this throttle, and the tip of this circular punch. The projection is for, the lower side of the narrowed portion has an inverted conical shape, while the round punch is set to be longer than the length of the narrowed portion, and cold die steel is vacuum-quenched. Punch to do.